Machining and forming method for hybrid input shaft gear hub

Abstract

The invention discloses a machining forming method for a hybrid input shaft gear hub. The machining forming method comprises the following steps that blanking is conducted, and a pier blank is heated; the blank is stamped and preformed, a preformed blank with a preformed gear ring and a preformed shaft body which are arranged at the two ends respectively is formed, and the outer diameter of the preformed gear ring and the outer diameter of the preformed shaft body are both larger than the outer diameter of a gear hub set gear ring and the outer diameter of a shaft body; finish forging forming is conducted, the side walls of the inner side and the outer side of the preformed gear ring are made flat, a rib plate is synchronously forged, and a plurality of preformed hole forming grooves with the width larger than the set width of the special-shaped holes are forged in the rib plate; trimming excess materials on the outer side of the pre-formed gear ring on the finish forging forming blank are cut off, and special-shaped hole pre-holes are punched in the corresponding positions of the pre-hole forming grooves; expanding and extruding an internal spline of the preformed gear ring by adopting a cold extrusion process, synchronously extruding bulges at two orifices of the special-shaped hole pre-hole into the special-shaped hole pre-hole by adopting a pier extrusion process, and synchronously extruding orifice chamfers at two ends to form a special-shaped hole of which the size and the shape are consistent with those of the set special-shaped hole; and lathing.

Description

Technical Field

[0001] The present invention relates to the field of gear hub manufacturing, and in particular to a processing and forming method of a hybrid input shaft gear hub. Background Art

[0002] The hybrid input shaft gear hub is a key component in the transmission system, which transmits power between the engine, motor and transmission. The input shaft gear hub includes a gear hub body, one end of which is provided with an internal spline cylinder, and the other end is provided with a connecting shaft coaxial therewith; a plurality of special-shaped holes are circumferentially provided on the rib plate in the middle of the gear hub body, and the upper and lower ends of the special-shaped holes are chamfered in the axial direction and are concave or waist-shaped. At present, when manufacturing the input shaft gear hub, blanking, piercing, forging, punching, milling and chamfering of the milling hole mouth and cold extrusion are adopted. With the above-mentioned manufacturing method, all special-shaped holes cannot be processed simultaneously at one time, the entire processing time is long, and the precision is difficult to control, and the molding quality is poor. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a method for machining and forming a hybrid input shaft gear hub, so as to solve the problems that the method mainly adopted for the special-shaped holes on the existing input shaft gear hub has many steps, requires milling the holes and chamfering the hole mouths, has low machining accuracy and poor forming quality.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: A processing and forming method for a hybrid input shaft gear hub comprises the following steps: S1, blanking, and heating the blanked bar material to form a blank; S2, stamping and preforming the blank after blanking to form a preformed blank with a preformed gear ring and a preformed shaft body at both ends, wherein the outer diameters of the preformed gear ring and the preformed shaft body are both larger than the outer diameters of the gear ring and the shaft body set by the gear hub; S3, final forging the preformed blank to make the inner and outer side walls of the preformed gear ring flat, and synchronously forge a rib plate, and forge a plurality of pre-hole forming grooves with a width larger than the set width of the special-shaped hole on the rib plate, wherein the pre-hole forming groove and the opposite side of the pre-hole forming groove are both protruding from the rib plate main body, and the protrusion height and width are consistent; S4, using a trimming composite die to cut off the preformed gear ring on the final forging blank The flash excess on the outside of the formed gear ring is removed, and a pre-hole for a special-shaped hole is punched out at the corresponding position of each pre-hole forming groove. The diameter of the pre-hole for the special-shaped hole is larger than the set diameter of the special-shaped hole, and the sum of the volumes of the protrusions at the two orifices of the pre-hole for the special-shaped hole is larger than the difference between the volume of the pre-hole for the special-shaped hole and the volume of the special-shaped hole without chamfering; S5, the inner spline of the pre-formed gear ring is expanded and extruded by a cold extrusion process, and the protrusions at the two orifices of the pre-hole for the special-shaped hole are synchronously extruded into the pre-hole for the special-shaped hole by an piercing process, and the orifice chamfers at both ends are synchronously extruded to form a special-shaped hole with a size and shape consistent with the set special-shaped hole; S6, the pre-formed shaft body and the outer side of the pre-formed gear ring of the cold-extruded blank are machined to make the gear ring reach the designed thickness, and the shaft body is consistent with the designed shape and size, and the processing of the input shaft gear hub is completed. In this way, the gear hub is mainly processed through the processes of blanking, blanking, stamping preforming, final forging, trimming and stamping pre-hole forming, cold extrusion of internal splines and special-shaped holes, and blank turning. Among them, the outer diameter of the preformed gear ring formed by stamping preforming is larger than the set outer diameter, so that during the final forging, the rib plate and the pre-hole forming groove are thicker at the corresponding positions during forging and are not easy to deform; after the bulges are formed on the outer side of the pre-hole forming groove and the corresponding side position of the pre-hole forming groove during forging, the axial bulging and extrusion are pressurized during cold extrusion to press the volume of the two bulges into the gap between the special-shaped hole pre-hole and the extrusion punch to ensure the fit with the cold extrusion die, thereby ensuring the dimensional accuracy and roughness of the side of the special-shaped hole. The chamfer set at the end of the extrusion die during the bulging can extrude the chamfers of the orifices at both ends. In addition, while the special-shaped hole is being extruded, the internal spline is also extruded and formed simultaneously on one mold, which ensures the dimensional accuracy of the internal spline, the dimensional accuracy of the special-shaped hole, and the positional relationship between the spline and the special-shaped hole, eliminating the milling process used for the special-shaped hole before. It takes 15 minutes to mill one special-shaped hole. With punching + cold extrusion of special-shaped holes, it only takes 10 seconds to extrude one piece, which greatly improves efficiency. The diameter of the preformed gear ring is larger than the set diameter. When the internal spline is cold extruded, the gear ring thickness is thicker than the set thickness. The stress of the preformed gear ring is greater, and deformation will not occur due to excessive stress during the extrusion process.

[0005] Furthermore, in S1, the heating temperature of the bar is controlled between 1100-1150° C. In this way, the set temperature can ensure that the bar has good fluidity during subsequent forging and can be quickly deformed and shaped.

[0006] Furthermore, before S5 cold extrusion, the blank after trimming and punching is first normalized, shot blasted, and turned, and then phosphating and saponifying. During normalizing, the temperature in the normalizing zone is 935±15℃, and the fan speed in the cooling zone is 50±5, ensuring that the product hardness is below 170HB; shot blasting uses ordinary 0.6mm steel shots to roll the product for about 20-30 minutes to ensure that the oxide scale on the surface of the product is clean and avoid residual oxide scale, which causes pits and scratches on the surface of the product after extrusion; the turning requires the coaxiality of the outer circle and the tooth shape to be within 0.05mm to ensure that the tooth shape accuracy of the product during extrusion meets the requirements of the drawing; ensuring a suitable lubrication concentration during phosphating and saponifying can facilitate smooth extrusion of the product and better surface quality of the product after extrusion.

[0007] The above process has the following advantages: 1. Improve precision: The extrusion process can effectively correct the dimensional deviation after punching and improve the precision of the hole. 2. Improve surface quality. The plastic deformation during the extrusion process can significantly improve the surface roughness of the special-shaped hole. 3. Enhance mechanical properties. The extrusion process can make the material structure around the hole denser and improve mechanical properties.

[0008] Furthermore, in S6, turning includes two rough turnings and two fine turnings. During rough turning, the reference surface of the product must be confirmed, the product tooth shape and the special reference surface after cold extrusion must be used as the clamping reference, and special tooling is made to ensure that the radial runout and end face runout of the tooling are ≤0.02mm, and the parallelism of the base surface after rough turning is ≤0.1mm; the clamping reference used in fine turning shall continue to use the rough turning reference, and the equipment is required to be installed with an airtight sensitivity detection device during fine turning, with a sensitivity setting of <0.1mm, to ensure that the product is clamped correctly during turning, and the product is not allowed to be clamped crookedly. Before each shift, the end runout and radial runout of the tooling are checked, and the end runout and radial runout are required to be <0.02mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Schematic diagram of the three-dimensional structure of the hybrid input shaft gear hub in the embodiment; Figure 2 is a schematic diagram of the cross-sectional structure of the hybrid input shaft gear hub in the embodiment; Figure 3 It is a process step diagram of forming and manufacturing the hybrid input shaft gear hub in the embodiment; Figure 4 It is a structural diagram of the blank after trimming and cold extrusion in the forming and manufacturing method S4 of the hybrid input shaft gear hub in the embodiment. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0011] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0012] like Figure 1-Figure 4As shown, the processing and forming method of the hybrid input shaft gear hub provided in this embodiment includes the following steps: S1, cutting the material by a high-speed circular saw, and heating the cut bar material to form a blank; S2, stamping and preforming the blank after the blanking, to form a preformed blank with a preformed gear ring and a preformed shaft body at both ends, wherein the outer diameters of the preformed gear ring and the preformed shaft body are both larger than the outer diameters of the gear ring and the shaft body set by the gear hub; S3, final forging the preformed blank to make the inner and outer side walls of the preformed gear ring flat, and synchronously forge a rib plate, and forge a plurality of pre-hole forming grooves with a width larger than the set width of the special-shaped hole on the rib plate (the shape of the pre-hole forming groove is the same as the shape of the preset special-shaped hole, such as Figure 3 As shown in the figure), the pre-hole forming groove and the opposite side of the pre-hole forming groove are both protruded from the rib plate body, and the protrusion height and width are consistent; S4, a trimming composite die is used to cut off the flash excess on the outer side of the pre-formed gear ring on the final forging blank, and a special-shaped hole pre-hole is punched out at the corresponding position of each pre-hole forming groove, the diameter of the special-shaped hole pre-hole is larger than the set diameter of the special-shaped hole, and the sum of the volumes of the protrusions at the two orifices of the special-shaped hole pre-hole is larger than the difference between the volume of the special-shaped hole pre-hole and the volume of the special-shaped hole in the unchamfered state (i.e., the attached Figure 4As shown in the figure, V1+V2>V3, wherein V3 is the difference between the volume of the pre-hole of the special-shaped hole and the volume of the special-shaped hole in the unchamfered state, the volume of V1=the bottom area of ​​the circumferential protrusion step S1×the step height H1, the volume of V2=the bottom area of ​​the circumferential protrusion S2×the step height H2); S5, the inner spline of the pre-formed gear ring is extruded by a cold extrusion process, and at the same time, the protrusions at the two orifices of the pre-hole of the special-shaped hole are synchronously extruded into the pre-hole of the special-shaped hole by an piercing process, and the orifice chamfers at both ends are synchronously extruded to form a special-shaped hole with a size and shape consistent with the set special-shaped hole; S6, the pre-formed shaft body and the outer side of the pre-formed gear ring of the cold extruded blank are machined to make the gear ring reach the designed thickness and the shaft body consistent with the designed shape and size, thereby completing the processing of the input shaft gear hub. In this way, the gear hub is mainly processed through the processes of blanking, blanking, stamping preforming, final forging, trimming and stamping pre-hole forming, cold extrusion of internal splines and special-shaped holes, and blank turning. Among them, the outer diameter of the preformed gear ring formed by stamping preforming is larger than the set outer diameter, so that during the final forging, the rib plate and the pre-hole forming groove are thicker at the corresponding positions during forging and are not easy to deform; after the bulges are formed on the outer side of the pre-hole forming groove and the corresponding side position of the pre-hole forming groove during forging, the axial bulging and extrusion are pressurized during cold extrusion to press the volume of the two bulges into the gap between the special-shaped hole pre-hole and the extrusion punch to ensure the fit with the cold extrusion die, thereby ensuring the dimensional accuracy and roughness of the side of the special-shaped hole. The chamfer set at the end of the extrusion die during the bulging can extrude the chamfers of the orifices at both ends. In addition, while extruding the special-shaped hole, the internal spline is also expanded and extruded, and formed simultaneously on one mold, which ensures the dimensional accuracy of the internal spline, the dimensional accuracy of the special-shaped hole, and the positional relationship between the spline and the special-shaped hole, eliminating the milling process used for the special-shaped hole before. It takes 15 minutes to mill one special-shaped hole. By using punching + cold extrusion of special-shaped holes, it only takes 10 seconds to extrude one piece, which greatly improves efficiency. The diameter of the preformed gear ring is larger than the set diameter. When cold extruding the internal spline, the thickness of the gear ring is thicker than the set thickness, and the stress of the preformed gear ring is greater, and it will not deform due to excessive stress during the extrusion process. When trimming and punching the special-shaped hole pre-hole, in order to reduce the deformation of the punching, a spring is designed to axially pressurize the rib plate to prevent deformation. In order to ensure that there is no punching tear on the punching side, a rounded corner R is designed at the front end of the punch, and the punching principle is used.

[0013] Furthermore, in S1, the heating temperature of the bar is controlled between 1100-1150° C. In this way, the set temperature can ensure that the bar has good fluidity during subsequent forging and can be quickly deformed and shaped.

[0014] Furthermore, before S5 cold extrusion, the blank after trimming and punching is first normalized, shot blasted, and turned, and then phosphating and saponifying. During normalizing, the temperature of the normalizing zone is 935±15℃, and the fan speed of the cooling zone is 50±5HZ to ensure that the product hardness is below 170HB; shot blasting uses ordinary 0.6mm steel shots to roll the product for about 20-30 minutes to ensure that the oxide scale on the surface of the product is clean and avoid residual oxide scale, which will cause pits and scratches on the surface of the product after extrusion; the turning requires the coaxiality of the outer circle and the tooth shape to be within 0.05mm to ensure that the tooth shape accuracy of the product during extrusion meets the requirements of the drawing; ensuring a suitable lubrication concentration during phosphating and saponifying can facilitate smooth extrusion of the product and better surface quality of the product after extrusion.

[0015] Furthermore, in S6, turning includes two rough turnings and two fine turnings. During rough turning, the reference surface of the product must be confirmed, the product tooth shape and the special reference surface after cold extrusion must be used as the clamping reference, and special tooling is made to ensure that the radial runout and end face runout of the tooling are ≤0.02mm, and the parallelism of the base surface after rough turning is ≤0.1mm; the clamping reference used in fine turning shall continue to use the rough turning reference, and the equipment is required to be installed with an airtight sensitivity detection device during fine turning, with a sensitivity setting of <0.1mm, to ensure that the product is clamped correctly during turning, and the product is not allowed to be clamped crookedly. Before each shift, the end runout and radial runout of the tooling are checked, and the end runout and radial runout are required to be <0.02mm.

[0016] Specifically, in this application, the first rough turning and the second rough turning are performed after the first rough turning and the second fine turning. After the above operations are completed, sorting, final inspection, cleaning and rust removal, and packaging and storage are performed.

[0017] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the technical solution. Those skilled in the art should understand that those modifications or equivalent substitutions of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution should be included in the scope of the claims of the present invention.

Claims

1. A method for processing and forming a hybrid input shaft gear hub, characterized in that: The method comprises the following steps: S1, blanking, and heating the blanked bar material to form a blank; S2, stamping and preforming the blank after blanking to form a preformed blank with a preformed gear ring and a preformed shaft body at both ends, wherein the outer diameters of the preformed gear ring and the preformed shaft body are both larger than the outer diameters of the gear ring and the shaft body set by the gear hub; S3, final forging the preformed blank to make the inner and outer side walls of the preformed gear ring flat, and synchronously forge a rib plate, and forge a plurality of pre-hole forming grooves with a width larger than the set width of the special-shaped hole on the rib plate, wherein the pre-hole forming groove and the opposite side of the pre-hole forming groove are both protruded from the rib plate main body, and the protrusion height and width are consistent; S4, using a trimming composite die to cut off the flying parts on the outer side of the preformed gear ring on the final forged blank The edge scraps are removed, and special-shaped hole pre-holes are punched out at the corresponding positions of each pre-hole forming groove. The diameter of the special-shaped hole pre-hole is larger than the set diameter of the special-shaped hole, and the sum of the volumes of the protrusions at the two hole openings of the special-shaped hole pre-hole is larger than the difference between the volume of the special-shaped hole pre-hole and the volume of the special-shaped hole without chamfering; S5, the inner spline of the pre-formed gear ring is expanded and extruded by the cold extrusion process, and the protrusions at the two hole openings of the special-shaped hole pre-hole are synchronously extruded into the special-shaped hole pre-hole by the piercing process, and the chamfers of the hole openings at both ends are synchronously extruded to form a special-shaped hole with a size and shape consistent with the set special-shaped hole; S6, the pre-formed shaft body and the outer side of the pre-formed gear ring of the cold-extruded blank are machined to make the gear ring reach the designed thickness and the shaft body consistent with the designed shape and size, and the processing of the input shaft gear hub is completed.

2. The method for machining and forming a hybrid input shaft gear hub according to claim 1, characterized in that: In S1, the heating temperature of the rod is controlled between 1100-1150°C.

3. The method for machining and forming a hybrid input shaft gear hub according to claim 1 or 2, characterized in that: Before S5 cold extrusion, the blank after trimming and punching is first normalized, shot blasted, and turned, and then phosphating and saponifying. During normalizing, the temperature in the normalizing zone is between 910-935℃, and the fan speed in the cooling zone is 45-55HZ to ensure that the product hardness is below 170HB; shot blasting uses ordinary 0.6mm steel shots to roll the product for 20-30 minutes; the turning requires the coaxiality of the outer circle and the tooth shape to be within 0.05mm to ensure that the tooth shape accuracy of the product during extrusion meets the requirements of the drawing; during phosphating and saponifying, ensure appropriate lubrication concentration.

4. The method for machining and forming a hybrid input shaft gear hub according to claim 3, characterized in that: In S6, turning includes two rough turnings and two fine turnings. During rough turning, the datum surface of the product must be confirmed. The tooth shape of the product and the datum surface after cold extrusion are used as the clamping datum, and the preformed gear ring is turned using a tool. During turning, the radial runout and end face runout of the tool are ≤0.02mm, and the parallelism of the base surface after rough turning is ≤0.1mm; during fine turning, the clamping datum used is the same as the rough turning datum, and the equipment is required to be installed with an airtight sensitivity detection device during fine turning. The tool sensitivity setting is <0.1mm, and the end runout and radial runout of the tool are required to be <0.02mm.

Images